diff options
| -rw-r--r-- | drivers/target/target_core_user.c | 213 | ||||
| -rw-r--r-- | include/uapi/linux/target_core_user.h | 7 |
2 files changed, 200 insertions, 20 deletions
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index e58127b8db8a..e080cd1a8fde 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -87,6 +87,8 @@ /* Default maximum of the global data blocks(512K * PAGE_SIZE) */ #define TCMU_GLOBAL_MAX_BLOCKS (512 * 1024) +static u8 tcmu_kern_cmd_reply_supported; + static struct device *tcmu_root_device; struct tcmu_hba { @@ -95,6 +97,13 @@ struct tcmu_hba { #define TCMU_CONFIG_LEN 256 +struct tcmu_nl_cmd { + /* wake up thread waiting for reply */ + struct completion complete; + int cmd; + int status; +}; + struct tcmu_dev { struct list_head node; struct kref kref; @@ -135,6 +144,11 @@ struct tcmu_dev { struct timer_list timeout; unsigned int cmd_time_out; + spinlock_t nl_cmd_lock; + struct tcmu_nl_cmd curr_nl_cmd; + /* wake up threads waiting on curr_nl_cmd */ + wait_queue_head_t nl_cmd_wq; + char dev_config[TCMU_CONFIG_LEN]; }; @@ -178,16 +192,128 @@ static const struct genl_multicast_group tcmu_mcgrps[] = { [TCMU_MCGRP_CONFIG] = { .name = "config", }, }; +static struct nla_policy tcmu_attr_policy[TCMU_ATTR_MAX+1] = { + [TCMU_ATTR_DEVICE] = { .type = NLA_STRING }, + [TCMU_ATTR_MINOR] = { .type = NLA_U32 }, + [TCMU_ATTR_CMD_STATUS] = { .type = NLA_S32 }, + [TCMU_ATTR_DEVICE_ID] = { .type = NLA_U32 }, + [TCMU_ATTR_SUPP_KERN_CMD_REPLY] = { .type = NLA_U8 }, +}; + +static int tcmu_genl_cmd_done(struct genl_info *info, int completed_cmd) +{ + struct se_device *dev; + struct tcmu_dev *udev; + struct tcmu_nl_cmd *nl_cmd; + int dev_id, rc, ret = 0; + bool is_removed = (completed_cmd == TCMU_CMD_REMOVED_DEVICE); + + if (!info->attrs[TCMU_ATTR_CMD_STATUS] || + !info->attrs[TCMU_ATTR_DEVICE_ID]) { + printk(KERN_ERR "TCMU_ATTR_CMD_STATUS or TCMU_ATTR_DEVICE_ID not set, doing nothing\n"); + return -EINVAL; + } + + dev_id = nla_get_u32(info->attrs[TCMU_ATTR_DEVICE_ID]); + rc = nla_get_s32(info->attrs[TCMU_ATTR_CMD_STATUS]); + + dev = target_find_device(dev_id, !is_removed); + if (!dev) { + printk(KERN_ERR "tcmu nl cmd %u/%u completion could not find device with dev id %u.\n", + completed_cmd, rc, dev_id); + return -ENODEV; + } + udev = TCMU_DEV(dev); + + spin_lock(&udev->nl_cmd_lock); + nl_cmd = &udev->curr_nl_cmd; + + pr_debug("genl cmd done got id %d curr %d done %d rc %d\n", dev_id, + nl_cmd->cmd, completed_cmd, rc); + + if (nl_cmd->cmd != completed_cmd) { + printk(KERN_ERR "Mismatched commands (Expecting reply for %d. Current %d).\n", + completed_cmd, nl_cmd->cmd); + ret = -EINVAL; + } else { + nl_cmd->status = rc; + } + + spin_unlock(&udev->nl_cmd_lock); + if (!is_removed) + target_undepend_item(&dev->dev_group.cg_item); + if (!ret) + complete(&nl_cmd->complete); + return ret; +} + +static int tcmu_genl_rm_dev_done(struct sk_buff *skb, struct genl_info *info) +{ + return tcmu_genl_cmd_done(info, TCMU_CMD_REMOVED_DEVICE); +} + +static int tcmu_genl_add_dev_done(struct sk_buff *skb, struct genl_info *info) +{ + return tcmu_genl_cmd_done(info, TCMU_CMD_ADDED_DEVICE); +} + +static int tcmu_genl_reconfig_dev_done(struct sk_buff *skb, + struct genl_info *info) +{ + return tcmu_genl_cmd_done(info, TCMU_CMD_RECONFIG_DEVICE); +} + +static int tcmu_genl_set_features(struct sk_buff *skb, struct genl_info *info) +{ + if (info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]) { + tcmu_kern_cmd_reply_supported = + nla_get_u8(info->attrs[TCMU_ATTR_SUPP_KERN_CMD_REPLY]); + printk(KERN_INFO "tcmu daemon: command reply support %u.\n", + tcmu_kern_cmd_reply_supported); + } + + return 0; +} + +static const struct genl_ops tcmu_genl_ops[] = { + { + .cmd = TCMU_CMD_SET_FEATURES, + .flags = GENL_ADMIN_PERM, + .policy = tcmu_attr_policy, + .doit = tcmu_genl_set_features, + }, + { + .cmd = TCMU_CMD_ADDED_DEVICE_DONE, + .flags = GENL_ADMIN_PERM, + .policy = tcmu_attr_policy, + .doit = tcmu_genl_add_dev_done, + }, + { + .cmd = TCMU_CMD_REMOVED_DEVICE_DONE, + .flags = GENL_ADMIN_PERM, + .policy = tcmu_attr_policy, + .doit = tcmu_genl_rm_dev_done, + }, + { + .cmd = TCMU_CMD_RECONFIG_DEVICE_DONE, + .flags = GENL_ADMIN_PERM, + .policy = tcmu_attr_policy, + .doit = tcmu_genl_reconfig_dev_done, + }, +}; + /* Our generic netlink family */ static struct genl_family tcmu_genl_family __ro_after_init = { .module = THIS_MODULE, .hdrsize = 0, .name = "TCM-USER", - .version = 1, + .version = 2, .maxattr = TCMU_ATTR_MAX, .mcgrps = tcmu_mcgrps, .n_mcgrps = ARRAY_SIZE(tcmu_mcgrps), .netnsok = true, + .ops = tcmu_genl_ops, + .n_ops = ARRAY_SIZE(tcmu_genl_ops), }; #define tcmu_cmd_set_dbi_cur(cmd, index) ((cmd)->dbi_cur = (index)) @@ -989,6 +1115,9 @@ static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name) setup_timer(&udev->timeout, tcmu_device_timedout, (unsigned long)udev); + init_waitqueue_head(&udev->nl_cmd_wq); + spin_lock_init(&udev->nl_cmd_lock); + return &udev->se_dev; } @@ -1176,9 +1305,54 @@ static int tcmu_release(struct uio_info *info, struct inode *inode) return 0; } -static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, - int minor, int reconfig_attr, - const void *reconfig_data) +static void tcmu_init_genl_cmd_reply(struct tcmu_dev *udev, int cmd) +{ + struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; + + if (!tcmu_kern_cmd_reply_supported) + return; +relock: + spin_lock(&udev->nl_cmd_lock); + + if (nl_cmd->cmd != TCMU_CMD_UNSPEC) { + spin_unlock(&udev->nl_cmd_lock); + pr_debug("sleeping for open nl cmd\n"); + wait_event(udev->nl_cmd_wq, (nl_cmd->cmd == TCMU_CMD_UNSPEC)); + goto relock; + } + + memset(nl_cmd, 0, sizeof(*nl_cmd)); + nl_cmd->cmd = cmd; + init_completion(&nl_cmd->complete); + + spin_unlock(&udev->nl_cmd_lock); +} + +static int tcmu_wait_genl_cmd_reply(struct tcmu_dev *udev) +{ + struct tcmu_nl_cmd *nl_cmd = &udev->curr_nl_cmd; + int ret; + DEFINE_WAIT(__wait); + + if (!tcmu_kern_cmd_reply_supported) + return 0; + + pr_debug("sleeping for nl reply\n"); + wait_for_completion(&nl_cmd->complete); + + spin_lock(&udev->nl_cmd_lock); + nl_cmd->cmd = TCMU_CMD_UNSPEC; + ret = nl_cmd->status; + nl_cmd->status = 0; + spin_unlock(&udev->nl_cmd_lock); + + wake_up_all(&udev->nl_cmd_wq); + + return ret;; +} + +static int tcmu_netlink_event(struct tcmu_dev *udev, enum tcmu_genl_cmd cmd, + int reconfig_attr, const void *reconfig_data) { struct sk_buff *skb; void *msg_header; @@ -1192,11 +1366,15 @@ static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, if (!msg_header) goto free_skb; - ret = nla_put_string(skb, TCMU_ATTR_DEVICE, name); + ret = nla_put_string(skb, TCMU_ATTR_DEVICE, udev->uio_info.name); if (ret < 0) goto free_skb; - ret = nla_put_u32(skb, TCMU_ATTR_MINOR, minor); + ret = nla_put_u32(skb, TCMU_ATTR_MINOR, udev->uio_info.uio_dev->minor); + if (ret < 0) + goto free_skb; + + ret = nla_put_u32(skb, TCMU_ATTR_DEVICE_ID, udev->se_dev.dev_index); if (ret < 0) goto free_skb; @@ -1224,12 +1402,15 @@ static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, genlmsg_end(skb, msg_header); + tcmu_init_genl_cmd_reply(udev, cmd); + ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, TCMU_MCGRP_CONFIG, GFP_KERNEL); - /* We don't care if no one is listening */ if (ret == -ESRCH) ret = 0; + if (!ret) + ret = tcmu_wait_genl_cmd_reply(udev); return ret; free_skb: @@ -1324,8 +1505,7 @@ static int tcmu_configure_device(struct se_device *dev) */ kref_get(&udev->kref); - ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name, - udev->uio_info.uio_dev->minor, 0, NULL); + ret = tcmu_netlink_event(udev, TCMU_CMD_ADDED_DEVICE, 0, NULL); if (ret) goto err_netlink; @@ -1414,8 +1594,7 @@ static void tcmu_destroy_device(struct se_device *dev) tcmu_blocks_release(udev); if (tcmu_dev_configured(udev)) { - tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name, - udev->uio_info.uio_dev->minor, 0, NULL); + tcmu_netlink_event(udev, TCMU_CMD_REMOVED_DEVICE, 0, NULL); uio_unregister_device(&udev->uio_info); } @@ -1600,9 +1779,7 @@ static ssize_t tcmu_dev_config_store(struct config_item *item, const char *page, /* Check if device has been configured before */ if (tcmu_dev_configured(udev)) { - ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE, - udev->uio_info.name, - udev->uio_info.uio_dev->minor, + ret = tcmu_netlink_event(udev, TCMU_CMD_RECONFIG_DEVICE, TCMU_ATTR_DEV_CFG, page); if (ret) { pr_err("Unable to reconfigure device\n"); @@ -1639,9 +1816,7 @@ static ssize_t tcmu_dev_size_store(struct config_item *item, const char *page, /* Check if device has been configured before */ if (tcmu_dev_configured(udev)) { - ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE, - udev->uio_info.name, - udev->uio_info.uio_dev->minor, + ret = tcmu_netlink_event(udev, TCMU_CMD_RECONFIG_DEVICE, TCMU_ATTR_DEV_SIZE, &val); if (ret) { pr_err("Unable to reconfigure device\n"); @@ -1677,9 +1852,7 @@ static ssize_t tcmu_emulate_write_cache_store(struct config_item *item, /* Check if device has been configured before */ if (tcmu_dev_configured(udev)) { - ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE, - udev->uio_info.name, - udev->uio_info.uio_dev->minor, + ret = tcmu_netlink_event(udev, TCMU_CMD_RECONFIG_DEVICE, TCMU_ATTR_WRITECACHE, &val); if (ret) { pr_err("Unable to reconfigure device\n"); diff --git a/include/uapi/linux/target_core_user.h b/include/uapi/linux/target_core_user.h index 4bfc9a1b635c..24a1c4ec2248 100644 --- a/include/uapi/linux/target_core_user.h +++ b/include/uapi/linux/target_core_user.h @@ -131,6 +131,10 @@ enum tcmu_genl_cmd { TCMU_CMD_ADDED_DEVICE, TCMU_CMD_REMOVED_DEVICE, TCMU_CMD_RECONFIG_DEVICE, + TCMU_CMD_ADDED_DEVICE_DONE, + TCMU_CMD_REMOVED_DEVICE_DONE, + TCMU_CMD_RECONFIG_DEVICE_DONE, + TCMU_CMD_SET_FEATURES, __TCMU_CMD_MAX, }; #define TCMU_CMD_MAX (__TCMU_CMD_MAX - 1) @@ -143,6 +147,9 @@ enum tcmu_genl_attr { TCMU_ATTR_DEV_CFG, TCMU_ATTR_DEV_SIZE, TCMU_ATTR_WRITECACHE, + TCMU_ATTR_CMD_STATUS, + TCMU_ATTR_DEVICE_ID, + TCMU_ATTR_SUPP_KERN_CMD_REPLY, __TCMU_ATTR_MAX, }; #define TCMU_ATTR_MAX (__TCMU_ATTR_MAX - 1) |